1 


THE  STUDY  OF  ASPHALTENE  IN  GILSONITE 


BY 

ERROL  BATHURST  MIDDLETON 
B.  A.  University  of  Illinois 


1919 


THESIS 

Submitted  in  Partial  Fulfillment  of  the  Requirements  for  the 

Degree  of 

MASTER  OF  SCIENCE 

IN 

CHEMISTRY 

IN 

THE  GRADUATE  SCHOOL 

OF  THE 

UNIVERSITY  OF  ILLINOIS 


1921 


' 


% 


m\ 

UNIVERSITY  OF  ILLINOIS 


THE  GRADUATE  SCHOOL 


June  2,  1921 


I HEREBY  RECOMMEND  THAT  THE  THESIS  PREPARED  UNDER  MY 


SUPERVISION  BY .Srrol  Bathurst  ki&dleton 


ENTITLED  Study  of  Asphaltene  in  Gilsonite . ” 


BE  ACCEPTED  AS  FULFILLING  THIS  PART  OF  THE  REQUIREMENTS  FOR 
THF  npr.RFF  OT7  Master  of  Science  in  Chemistry 


u y.  ^ 


/ 


In  Charge  of  Thesis 


Head  of  Department 


Recommendation  concurred  in* 


Committee 

on 

Final  Examination* 


Required  for  doctor’s  degree  but  not  for  master’s 


Digitized  by  the  Internet  Archive 
in  2015 


https://archive.org/details/studyofasphaltenOOmidd 


ACM  OWLED  G-MEN  2 

I take  this  opportunity  to  thank  Professor  S.  W.  Parr  for  the 
valuable  assistance  and  kindly  suggestions , which  he  so  freely 
gave  at  all  times  during  this  investigation. 

I am  also  indebted  to  the  American  Asphalt  Association  who 
furnished  the  materials  used  in  this  research. 


. 


TABLE  OE  COL  LEFTS 


IF  PRODUCTION 

Geology  of  Gilsonite 

Composition  of  Gilsonite 
Mining 

Uses  of  Gilsonite 

HISTORICAL  PART 
SOLVENTS  AND  SOLUBILITY 

GG14*  and  its  Use  as  a Solvent  for  Different  iat- 
ing  Bitumens 

G32  as  a Solvent  in  the  Analysis  of  Bitumens 

Solubility  in  88°  D aphtha  or  Hexane 

Other  Solvents 

EXPERIMED TAD  PART  ■ 

Methods  of  Examination  of  Asphalts 

Methods  of  Analysis  of  Gilsonite  by  Hexane 

Centrifugal  Method  of  Analysis  of  Gilsonite 

Discussion  of  Methods 

Method  of  Determining  Sulfur 

Fit  no  gen 

0 RIGID  OE  ASPHALTEDES  , THEIR  PROPERTIES  ADD  COMPOSITION 
SUMMARY 


Page 

1 

1 

2 

2 

4 

6 

6 

7 

7 

8 
9 

13 

15 

17 

17 

19 


23 


BIBLIOGRAPHY 

ACKNOWLEDGMENT 


25 


' 


, 


1- 


THE  STUDY  CD  ASPHATENE  IE  GIL  SOU  ITE 
INTRODUCTION 
Geology  of  Gilsonite . 

Gilsonite  is  a solid  natural  bitumen  not  distributed  very 
widely  in  nature.  It  is  the  result  of  metamorphism  of  petroleum 
under  pressure , and  is  found  in  fissure  veins  which  approach  the 
vertical  and  afford  the  conditions  which  are  favorable  for  the 
metamorphosis  of  petroleum  into  those  materials.  Grahamite, 
another  solid  native  bitumen  is  also  found  in  nature. 

The  change  has  gone  on  under  a varying  time  factor,  to  an 
extent  that  has  resulted  in  substances  presenting  different  degrees 
of  condensation , from  one  which  flows  softly  in  the  sun,  as  is  the 
case  with  our  softest  .Gilsonite,  to  one  of  the  hardness  of  the 
brittlest  Grahamite,  which  does  not  melt  at  even  the  highest 
temperatures . 

Composition  of  Gilsonite  . 

xhis  mineral  is  a hydrocarbon  and  is  found  in  commercial 
quantities  in  the  immediate  vicinity  of  Dragon , Utah.  It  is  shipp- 
ed in  two  grades,  select  Gilsonite,  and  Gilsonite.  The  grading 
is  done  at  the  mines  and  by  appearance  only,  but  this  is  sufficient 
for  the  appearance  of  each  grade  is  so  characteristic  that  there  is 
a small  chance  for  error.  Occasionally  a melting  point  is  taken 
to  check  up  on  the  ore.  The  selects  are  taken  from  the  center  of 
the  vein  and  are  characterized  by  a conchoidal  and  lustrous  fracture* 
The  seconds  occur  near  the  edge,  and  have  a semi-conchoidal  and 
semi-lustrous  fracture.  In  other  respects  they  are  alike. 

Of  the  two  grades  of  Gilsonite,  the  select  is  in  much  more 
demand,  because  it  is  more  suitable  to  use  in  paints  and  varnishes. 


* 


2- 


Very  few  paint  and  varnish  makers  can  use  Gilsonite  at  all.  Gil- 
sonite  is  used  in  the  manufacture  of  roofing  compounds,  and  this 
use  distinguishes  it  from  the  higher  grade  select  Gilsonite. 

Mining. 

The  methods  of  mining  Gilsonite  are  very  crude.  It  is  done 
with  a pick  and  shovel,  together  with  some  sort  of  simple  hoisting 
apparatus.  Very  little  timber  is  required,  as  the  veins  are 
nearly  vertical,  and  the  surrounding  rock  is  firm  and  self-support- 
ing. Prom  this  Utah  source,  20,000  tons  of  Gilsonite  are  mined 
and  shipped  annually , -value  approximately  §65,000.  There  are 
52,000,000  tons  of  Gilsonite  left  in  the  region,  according  to 
Abraham,  "Asphalts  and  Allied  Substances",  page  155. 

Uses  of  Gilsonite . 

The  general  method  for  making  permanent  coverings  using  Gil- 
sonite Selects  is  to  melt  the  selects  down  to  a flux,  usually 
rosin  and  then  the  mixture  is  thinned  d own  with  benzine  and  an  oil, 
usually  chinawood  oil  or  linseed  oil.  Every  varnish  and  paint 
maker  has  his  own  formula. 

Select  Gilsonite  has  a lower  melting  point,  and  is  more  soluble 
than  Gilsonite.  For  these  reasons  it  is  in  demand  by  the  paint  or 
varnish  maker.  Since  Gilsonite  is  more  easily  mined  than  Select 
Gilsonite  and  is  lower  priced  it  would  greatly  benefit  the  entire 
paint  industry,  if  a method  could  be  obtained  whereby  Gilsonite 
could  be  changed  to  select  Gilsonite. 

Besides  its  use  in  paint  and  varnishes,  and  roofing,  Gilsonite 
has  successfully  been  used  in  the  paving  industry,  and  it  is  well 
to  note  its  use  here,  because  of  the  number  of  road  treatment 

preparations  which  use  it  as  a binding  base.  It  can  "be  used  with- 


3- 


out  refining  for  this  purpose.  It  is  also  used  in  the  manufacture 

of  electric  insulators,  for  acid  proofing,  and  in  instances  where 

we  want  a smooth,  elastic  resistant  and  weatherable  coating. 

Its  physical  and  chemical  properties  are  on  the  average: 

Table  I.  Analysis  and  Examination  of  Gilsonite. 

Sp.  Gr.  1.04 

Softens  127-149 

Plows  134-164 

loss  at  63°G . ( 7 hrs . ) .4$-6.5 $ 

loss  at  205°0 . ( 7 hrs.)  1.0$-2.0$ 

Character  of  residue  at  65°G  and  205°C.  Smooth 

Bitumen  (90 $ Soluble  in  CS£ 

( 7 $ Organi c Hat  ter 


Inorganic  Matter  3 $ 

Percent  Bitumen  Insoluble  in  CC1Z.  0-0. 4$ 

Pixed  Carbon  14$ 

Sulfur  .66$ 

According  to  G.  C.  Austin,  General  Manager  of  the  American 
Asphalt  Association,  the  chief  difference  between  the  two  grades 
of  Gilsonite  is  in  the  percentage  of  "malt^enes"  or  "petrolenes” 
present.  These  materials  are  soluble  in  hexane.  The  Gilsonite 
selects  are  supposed  to  have  a higher  percentage  of  "malt/enes"  than 
the  lower  grade.  If  this  be  the  case,  certain  steps  or  measures 
might  be  taken  to  remedy  this.  Maltha  may  be  added,  if  need  be, 
or  a heavy  as -o halt  oil. 


. 


- 


< 


4- 


HISTORICJAL  PART 

In  1837,  Boussingault , a Frenchman,  published  a memoir  of  the 
composition  of  bitumens.  He  discovered  that  certain  bitumens 
yielded  a portion  of  their  constituent  hydrocarbons  to  one  class  of 
solvents,  and  another  portion  to  another  class.  He  called  one 
portion  "asphaltene"  , and  the  other  portion  "petrolene " . The 
conclusions  that  he  drew  from  his  work  was  that  these  two  substances 
were  simple,  and  also  that  they  were  identical  from  whatever  source 
obtained.  However,  indications  pointed  that  "petrolene"  is  but  a 
name  that  covers  a multitude  of  substances,  decidedly  unlike,  which 
exist  in  different  forms  of  bitumen,  and  are  only  related  in  this 
instance,  as  being  held  in  solution  by  a limited  number  of  solvents, 
and  it  includes  the  whole  list  of  paraffins,  iso-paraffins,  ben- 
zenes, olefines,  and  additive  benzenes , with  many  other  less 
abundant  and  well  known  substances.  The  solvents  for  petrolene 
are  ethyl  ether,  petroleum,  naphtha.  Petrolene  is  nothing  but  a 
name . 

In  1827,  LeBel  and  Muntz  went  over  the  same  ground,  a nd  in  $ 
1883,  LeBel  went  over  it  again,  added  a few  facts  in  relation  to 
other  bitumens  than  those  which  had  been  examined.  He  left  the 
two  substances  asphaltene  and  petrolene  practically  where  he  found 

them. 

Laura  A.  Linton  showed  later  that  asphaltene  is  little  more 
definite  than  petrolene,  and  that  no  certainty  attaches  itself  to 
the  identity  of  asphaltene  from  different  sources  or  of  asphaltene 
dissolved  by  different  solvents. 

The  bitumens  examined  by  these  French  chemists,  LeBel  and 
Boussingault  never  assumed  any  commercial  importance.  This  re- 


5- 


search  was  purely  scientific  and  little  was  thought  that  the  chemi- 
cal examination  of  asphalts  would  ever  assume  any  great  importance. 
Since  asphalt  paving  has  "become  economically  important,  technolo- 
gists have  "begun  to  seriously  consider  the  question  of  a chemical 
examination  of  asphaltic  material,  and  the  problem  has  been  carried 
outside  the  laboratory.  By  1894,  large  numbers  of  so-called 
analyses  had  appeared,  which  represent  various  attempts  to  determine 
and  set  forth  the  values  of  many  kinds,  and  samples  of  asphaltum, 
that  may  or  may  not  be  suitable  for  different  uses. 

Since  asphalts  are  mixtures  there  is  a great  danger  that  the 
product  could  be  adulterated,  and  the  chemical  examination  of 
asphalts  has  proved  an  obstacle  for  adulterators.  These  mixtures 
are  usually  based  on  the  fact  that  they  must  contain  Trinidad 
Asphalt.  The  substitutes  for  Trinidad  Asphalt  usually  contain 
Gilsonite  tempered  with  petroleum  residues,  and  are  only  suited  for 
a certain  class  of  work. 

Before  chemical  an  lysis  began  to  play  such  an  important  role 
in  the  asphalt  game,  a lew  physical  tests  on  mixtures  were  sufficient, 
The  first  avenue  of  approach,  as  to  the  chemistry  of  asphalt  mix- 
tures was  to  turn  the  attention  toward  organic  solvents  that  would 
indicate  the  chemical  nature  of  the  asphalt  mixture.  Up  to  the 
present  time,  the  methods  employed  are  not  satisfactory  methods  of 
chemical  analysis,  so  improvements  must  be  made  on  the  older  ones, 
or  new  ones  devised. 


6- 


3 OL VENTS  AND  SOLUBILITY 

CGI  , and  its  Use  as  a Solv ent  for  Differentiating 
4 Bitumens . 

CGl^  is  used  as  a substitute  for  GSg  in  the  dete rmina.t ion  of 
bitumens.  It  is  non-inflammable,  non-explosive,  has  an  aromatic 
odor,  low  vapor  tension,  and  no  toxic  effect,  while  GSg  is  very 
inflammable,  explosive,  has  a high  vapor  tension,  and  is  poisonous. 
CCl^  boils  at  46°G.  and  GSg  at  76.6°G.  Considered  as  a standard 

for  extraction  on  a commercial  scale  it  is  the  equal  in  solvent 
power  of  almost  all  other  solvents,  exceeding  them  with  certain 
substances . 

The  value  of  CCI4  as  a solvent  in  the  case  of  bitumens  lies 
in  the  fact  that  it  possesses  a selective  action  on  hydrocarbons. 
CCl^  will  dissolve  the  ma Irenes  or  petrolene  in  bitumen,  but  will 
have  no  effect  on  the  carbenes  . The  expression,  "carbenes"  , has 
been  applied  to  that  portion  of  bituminous  substances  soluble  in 
C3g  and  insoluble  in  GC1Z . They  are  the  result  of  over  heating 
or  over  blowing.  When  the  solvent  power  was  tried  on  Gilsonite , 
the  result  was  practically  the  same  as  with  GSp . So  the  Gilsonite 
contains  very  little  of  the  carbenes,  if  any  at  all. 

Garbon  Bisulfide  as  a Solvent  in  the  Analysis 
of  Bitumens . 

The  percentage  of  bitumens  soluble  in  GSg  is  useful  for  pur- 
poses of  identification,  for  ascertaining  the  adaptability  of  a 
bituminous  substance  for  certain  purposes,  for  a gauge  as  to  its 
uniformity  of  supply,  and  as  a means  of  judging  its  quality.  Crude 
bituminous  materials  are  purchased  sometimes  upon  the  basis  of  CS9 
soluble  bitumens.  In  the  case  of  certain  natural  asphalts,  the 
greater  the  percentage  solubility  in  G3g , the  greater  their  intrin- 


, 


7- 


sic  value.  Gilsonite  is  a solid  natural  "bitumen  approximately 
99 70  soluble  in  CSg.  CSg  may  exclude  mineral  matter  in  asphalts, 
so  the  Gilsonite  is  practically  free  from  mineral  matter. 

Solubility  in  GSg  is  a measure  of  purity  of  an  asphaltic 
cement.  The  cementing  value,  other  things  being  equal  is  propor- 
tional to  the  GSg  solubility.  Any  carbonaceous  material  such  as 
coal  tar  or  pitch  is  detected  by  the  GSg  solubility  test. 

Solubility  in  88°  K aphtha  or  Hexane . 

The  solubility  of  asphats  in  88°  petroleum  naphtha  is  a cri- 
terion of  the  percentage  of  malthenes  in  an  asphalt.  Asphaltites 
are  relatively  insoluble  in  this  solvent.  The  portion  of  asphalts 
insoluble  are  the  asphaltenes. 

Other  Solv ent  s . ( Solubility) 

Other  solvents,  than  those  just  mentioned,  as  turpentine, 
toluol,  benzol,  mixtures  of  benzol  and  toluol,  and  acetone  are 
sometimes  used  for  the  identification  of  certain  bitumens,  but 
are  not  as  successful  as  C3r . 


8- 


EKPEHIMEN  PAL  ( DI SCU3SI  OF ) 

Methods  of  Examination  of  Asphalts . 

The  presnet  chemical  knowledge  of  bituminous  substances  is 
very  limited.  Their  practical  chemistry  is  confined  to  the  most 
rudimentary  of  tests , based  on  rule  of  thumb  methods  rather  than 
on  an  accurate  scheme  of  chemical  analysis.  There  is  a woeful 
lack  of  scientific  analytical  methods. 

In  the  determination  of  asphalts,  the  term  percentage  of 
asphalt  has  not  as  yet  been  defined  in  chemical  terns.  It,  there- 
fore, cannot  be  determined  like  other  chemical  individuals.  The 
presnet  means  of  determining  asphalts  is  as  follows: 

(a)  Precipitation  with  petroleum  ether. 

(b)  Precipitation  with  alcohol-ether. 

(c)  In  case  of  soft  materials  evaporation  until  a certain 
consistency  is  reached. 

The  methods  "a"  and  "bn  tend  to  determine  the  percentage  of 
asphalt  by  a chemical  reaction,  precipitating  a part  of  the  same, 
while  the  last  method  tends  to  define  the  percentage  by  reducing 
the  bitumen  to  a certain  fixed  physical  consistency,  calling  any- 
thing asphalt  which  has  that  consistency  or  harder.  By  the  first 
method,  we  make  use  of  the  fact  that  the  so-called  "asphaltenes" 
are  insoluble  in  petroleum  ether,  and  therefore,  are  precipitated 
by  it,  v/hereas  the  petrolenes  are  soluble.  This  method  is  of 
course,  not  a direct  measure  for  the  real  composition  or  content 
of  the  asphalts,  as  it  permits  only  of  an  approximate  estimation 

of  the  same  by  the  percentages  of  asphaltenes,  unless  we  previously 
know  the  nature  of  the  bitumen.  If  the  asphaltic  material  to  be 
be  examined,  contains  some  light  petroleum  distillates,  then  a 


' - 


. 


r 


9- 


distillate  of  86°  to  88°  Be'  shows  less  asphaltenes  present. 

Methods  of  Analysis  of  Gil  son  it  e by  Hexane  Iletho  d . 

After  considerable  experimentation  with  different  solvents 
such  as  CS£ , GgHg , CCI4,  CHClg , and  toluene,  it  was  found  advisable 
to  use  GS£  (sulfur  free),  and  the  proper  condition  for  the  solvent 
action  of  0S£  and  the  precipitation  with  hexane  was  at  room  tem- 
perature. She  following  plan  of  analysis  was  suggested  from  the 
pamphlet  "The  Chemical  Examination  of  Asphaltic  Material",  by 
Prof.  3.  W.  Parr,  B.  Mears  , and  D.  1.  Weatherhead.  Half  gram 
samples  of  powdered  Gilsonite  was  placed  in  separatory  funnels  of 
a50  cc.  capacity,  and  5 cc.  CS£  was  added.  When  the  solution  is 
complete,  ICO  cc . hexane,  sp.  gr.  .66  (Westphal  balance)  are  added. 
The  mixture  is  allowed  to  stand  for  two  hours  and  a precipitate  is 
formed,  which  corresponds  to  the  asphaltenes  of  the  usual  methods. 
This  precipitate  is  next  thoroughtly  washed  with  hexane  and  filter- 
ed on  a specially  prepared  Gooch  crucible,  described  on  page  (16), 
which  is  dried  in  an  electric  oven  at  105°G.  to  constant  weight. 

This  is  possible  because  no  oxidation  or  chemical  action  has  taken 
place.  This  precipitate  calculated  in  terms  of  the  sample  was 
precipitate  #1.  , corresponding  to  the  asphaltenes  mentioned  above. 

Hexane  can  be  recovered  by  condensation  from  the  filtrate  ob- 
tained from  precipitate  ,1  where  CS£  is  used,  much  easier  than  the 
other  solvents  , and  the  recovered  hexane  can  be  used  again  very 
satisfactorily.  Recovery  yields  of  from  60-70$  of  the  amount  of 
hexane  used  can  be  obtained.  Since  both  hexane  and  CS£  are  highly 

inflarama  ole , the  source  of  heat  for  d 1st  ills,  t ion  is  from  an  electi*ic 
hot  plate  about  4"  in  diameter,  and  the  distilling  flask  a 250  cc. 

Erlenmeyer  flagk.  The  distillation  can  be  made  to  dryness. 


10- 


To  obtain  precipitate  # 2 , the  filtrate  from  the  preceding 
determination  can  be  evaporated  to  dryness. 

The  residue  is  next  taken  up  in  the  Erie nmeyer  flask  with 
10  cc . of  hexane,  while  the  flask  is  warm  and  poured  back  into  the 
original  separatory-  funnel.  A complete  transfer  can  be  made  with 
no  loss  of  material  or  solvent  . This  hexane  solution  while  still 
warm  is  allowed  to  run  slowly  into  500  cc.  of  methyl  alcohol,  in 
a glass  crystalliz  ing  dish,  previously  tared  , the  alcohol  having 
been  cooled  below  the  freezing  point  of  water.  The  alcohol  must 
be  constantly  agitated  and  stirred.  A sticky,  gummy,  black 
precipitate  is  obtained  which  collects  on  the  sides  of  the  dish. 
After  complete  precipitation  and  standing  for  two  hours,  the  al- 
cohol is  decanted  through  a weighed  Gooch  crucible  of  the  type  used 
for  precipitate  #1.  Both  the  dish  and  crucible  are  dried  at  1C5° 
and  weighed.  The  gain  in  weight  of  the  dish  and  crucible  repre- 
sents the  secnnd  precipitate  ..corresponding  to  the  mslthenes. 

Precipitate  #3  was  obtained  by  evaporating  the  methyl  alcohol 
from  the  second  determination  and  weighing  the  residue  in  a glass 
dish  ,and  contains  the  tarry  residues  of  the  Gilsonite. 

Table  #2 . Solubility  of  Gilsonite. 

Insoluble  in  GSg  Insoluble  in  CCI4  Insoluble  in  CHOI 9 

.4$  .4 $ 

.3  .5 


.35 

.17 

Chloroform: 

Takes  Gilsonite 

CS2: 

Takes  Gilsonite 


•16  .25 

.2  .3 

into  solution  very  rapidly. 

i-ho  solution,  but  not  quite  so  rapidly  as 


11- 


CHClg,  in  its  solvent  power. 

Benzene : 

Dissolves  Gilson ite  more  slowly  than  GSg  or  CHClg. 
Acetone : 

Acetone  has  only  a small  noticeable  effect. 

CC14: 

Similar  to  chloroform  in  its  behavior. 

Ether: 

Little  noticeable  effect. 


Samples  of  Gilsonite  from  the  museum  were  analyzed  according 
to  the  method  of  analysis  as  used  in  "The  Chemical  Examination  of 
Asphaltic  Material",  by  Prof.  3.  17.  Parr,  Barinerd  Hears,  and 
D.  L.  beatherhead . 


Table  III.  Gilsonite. 


Sample  Do 

. Ppt . trl 

Ppt.  #2 

Ppt . #3 

Total 

1 

Asphaltenes 

48  • 01% 

Malthenes 

40.71% 

Tarry  -e 
7 . 28% 

sidues 

96.00% 

2 

44.38 

43.63 

12.99 

100.00 

3 

43.27 

42.25 

8.35 

93.87 

Average 
of  each 

45.22 

42.19 

9.54 

96.62 

An  analysis  of  Gilsonite  for  precipitate  {=1 
using  special  care  for  the  determinat ion  of  this 
following  results  were  obtained: 

Table  IV.  Gilsonite. 
Sample  II  o.  Ppt . #1 


1 

2 

3 


Asphsltene  s 

45.95% 

46.83 

45.23 


alone  was  made , 
precipitate  and 


the 


average 


46.00 


12- 


Analyses  were  made  on  samples  of  Gilsonite  and  Gilsonite 
select  and  the  following  results  obtained; 


Table  V. 

Gilsonite  Select 

Ppt.  #1 
Asphaltenes 

11.2  $ 

Ppt.  #2 
Malthenes 
66.84  % 

Ppt.  #2 

Tarry  Residues 

16.24  % 

Total 
96.28  % 

12.2  % 

67.4 

15.04 

95.64  io 

11.46 

70.84 

15.16 

97  .46 

Average  11.95 

69.02 

15.48 

96.67 

Another  analysis  using  CCl^ 

in  place  of  CS^  was  made, and  tl 

following  result 

s obtained: 

Table  VI. 

Gilsonite 

Ppt.  #1 

Asphaltenes 
46.50  % 

Ppt.  #2 
Malthene s 
42.06  % 

Ppt.  #2 
Tarry  Residues 
9.52  % 

Total 
99.09  $ 

47.75 

42.25 

9.58 

99.59 

45.56 

42 .66 

10.45 

99.67 

Average  16.60 

42.79 

9.54 

99.78 

Table  Vll. 

Gilsonite 

45.20  fo 

44.66  % 

9.22  °]o 

99.19 

45.94 

44.24 

6.45 

98.62 

45.84 

42.72 

9.67 

98.24 

Average  45.69 

42.88 

9.12 

98.68 

The  above 

results  appear 

to  bear  the  assumption 

of  Mr. 

C.C. Walker  of  the  American  Asphalt  Co., which  is  that  the 
difference  between  the  two  grades  of  Gilsonite  is  due  to  the 
percentage  of  the  malthenes  or  Petrolemes. 

Numerous  runs  were  made  on  the  analysis  of  Gilsonite  and 
Gilsonite  select  with  varying  results.  Those  just  mentioned 
above  being  the  best 


- 


. 


13- 


fable  VIII. 

Gilsonite . 

Sample 

1 

Bo . Ppt . #1 

Asphaltenes, 

Ppt . # 2 Ppt . # 3 

Malthenes  Tarry  "Residues 
47.20#  7.60  fo 

Total 

87.05# 

2 

36.85 

38.03 

12.3 

87.05 

3 

27.25 

49.06 

6.2 

82.51 

4 

45.00 

39.25 

4.6 

88.85 

5 

39.20 

37.73 

11.45 

CO 

to 

• 

CO 

CO 

6 

28.03 

47.03 

12.36 

88.42 

7 

51.36 

27.00 

10.06 

88.32 

8 

42.48 

15.00 

57.48 

9 

37.39 

5.20 

42.59 

10 

44.74 

56.14 

8.66 

109.54 

11 

52.06 

32.59 

16.77 

101.41 

1 

Table  IX. 

Asphaltene  s 

5.25 

Gilsonite 

Malthene s 

76.93 

Select 

Tarry  Residues 
25.26 

91.27 

2 

6.34 

82.04 

12.36 

100.74 

3 

9.68 

53.38 

18.84 

81.90 

Centrifugal  Method  of  Analysis  of  Gilsonite . 

After  making  these  analyses,  a new  method  for  making  the  r re- 

e 

ci; it at ion  01  the  naphthalnefi  more  complete  suggested  itself. 

JProm  observing  the  lormaticn  and  precipitation  of  the  asphaltenes, 
and  novv  quickly  they  settled  out,  it  seemed  possible  that  the  re- 
precipitation might  still  further  be  hastened  if  they  were  centri- 
fuged . A few  Qualitative  runs  were  made,  using  a high  powered 
centrifuge,  -nd  it  was  found  that  a very  clean  cut  precipitate  would 
quickly  lorm,  and  that  the  natant  liquid  above  them  could  practically 


14- 


be  decanted.  The  asphaltenes  thus  obtained  could  be  easily  dried 
in  an  electric  oven  at  100°C.  The  occluded  or  adsorbed  solvent 
present  in  the  precipitate  made  it  very  bulky,  and  it  was  observed 
that  the  drying  at  100°3  would  cause  a noticeable  shrinkage.  A 
very  pure  product  may  be  obtained  this  way,  very  quickly. 

This  centrifuge  method  worked  very  satisfactorily,  quantita- 
tively, with  Gilsoriite  as  the  results  will  show.  An  analysis  for 
asphaltenes  alone  by  this  method  was  nn.de. 


Table  X.  Asphaltenes  in  Gilsonite. 

Sample  Mo. 

Ppt.  $ 

1 

ASp^?fes 

£ 

46.73 

3 

44.31 

Avera ge 

45. 4£ 

The  precipitation  of  an  asphaltene  can  be  easily  made  in  the 
glass  centrifuge  cups,  the  precipitate  centrifuged  out,  and  the 
hexane  easily  recovered  as  in  the  preceding  method.  Precipitate 
vf3  was  obtained  in  the  usual  manner.  Results  on  Gilsonite  by 

this  method: 


Table  XI.  Gilson ite  Select. 


Ppt.  #1 

Ppt . #2 

Ppt.  ''-3 

Total 

Asphaltenes 

11.33$ 

Malthenes 

70.00$ 

Tarry  Residues 

15.43$ 

96.76 $ 

10.56 

72.00 

14.73 

97.29 

11.05 

73.00 

15.28 

99.33 

Average  10.98 

71.66 

15.14 

. 97.13 

15- 


Discussion  of  Ifethods . 

In  the  analysis  of  asphalts  by  the  method  of  selective  organic 
solvents,  quite  a number  of  difficulties  have  to  be  contended  with. 
For  example,  in  the  precipitation  of  asphaltenes  from  a C3g  solu- 
tion by  means  of  petroleum  ether  or  hexane,  sp.  gr.  .66,  the  pre- 
cipitate obtained  is  colloidal  in  nature  , and  ver  difficult,  to 
remove,  usually  part  of  the  precipitate  pas.es  through  the  Gooch 
filtering  crucible.  (This  would  be  a source  of  considerable  error 
if  it  could  not  be  remedied.  It  may  be  remedied  in  this  way. 

The  reduced  pressure  creates  a freezing  of  the  hexane  in  the  filter 
flask,  and  the  asphaltene  precipitate  going  through  comes  in  con- 
tact with  this  freezing  mixture,  and  separates  out,  and  can  be 
refiltered  through  the  same  filtering  medium.  The  only  danger 
here  is  that  the  asphaltene  has  a tendency  to  stick  to  the  filter 
flask.  Pre.ctically  all  of  the  asphaltene  can  be  removed  by  this 
refiltering  process.  If  allowed  to  stand  for  any  length  of  time 
in  contact  with  gla^s,  the  asphaltenes  adhere  very  closely,  and  are 
very  difficult  to  remove  so  the  quicker  they  can  be  filtered,  after 
having  been  formed,  the  better. 

However,  at  best,  the  filtering  of  asphaltic  precipitates 
suspended  in  organic  solvents  is  a slow,  tedious  and  unsat  is  fact ory 
process.  The  following  simple  deviation  from  the  ordinary  method 
oi  preparing  Gooch  crucibles  was  used.  Ordinarj  ily  the  Gooch 
crucibles  are  prepared  as  shown  in  the  accompanying  illustration. 


' 


* 


■ 

. 


t 


16- 


^his  slight  change.  Pig.  2,  was  made,  and  proved  satisfactory  in 
the  laboratory. 


A thimble  cone  of  Gu  gauze  is  placed  in  the  bottom  of  a 
Gooch  crucible  and  the  asbestos  sucked  dry  over  it  as  shown  in  the 
figure.  In  cases  where  ignition  is  not  necessary,  as  in  our  case, 
the  copper  gauze  is  satisfactory.  Where  ignition  is  necessary, 
the  cone  should  be  made  of  Pt.  In  actual  practise,  the  cone  not 
only  gives  us  an  increased  surface  for  filtering,  but  also  allows 
the  heavier  and  denser  portion  of  the  precipitate  to  settle  in  a 
ring  at  the  bottom  of  the  crucible,  leaving  the  asbestos  on  the 
apex  of  the  filter,  in  such  a condition  that  the  filtrate  and  washing 
liquids  can  be  quickly  removed.  It  might  be  called  a fractional 
f ilt  er . 


It  is  very  difficult  to  obtain  duplicate  results  on  accout  of 
the  fact  that  it  is  very  hard  to  obtain  a uniform  homogeneous  sample 
of  such  a mixture  as  Gilsonite  or  Gilsonite  mixtures;  and  hard  to 
obtain  solvents  of  uniform  specific  gravity  and  composition. 

Table  XII.  Sulfur 

analyses  were  made  on  Gilsonite,  Gilsonite  Select,  and  the 
Asphaltenes  , and  the  following  results  obtained: 


Gilsonite 

Gilsonite  Select 

Asphal tene 

. 674# 

Sulfur  .637#  Sulfur 

.9605#  ; 

. 666 

.680 

.972 

.655 

.656 

.954 

.671 

.643 

.936 

17- 


Method  of  Determining  Sul  fur . 

The  sulfur  on  these  samples  was  determined  as  follower:  .2 

grams  samples  of  material  were  weighed,  and  fused  in  a peroxide 
fusion  bomb  with  1 gram  KCICg  , and  10-12  grams  of  Ba^Gc.  The 
fused  mass  was  dissolved  in  about  2C0  go.  of  distilled  water,  fil- 
tered to  remove  any  insoluble  matter,  treated  with  10-20  cc.  sat- 
urated bromine  water,  and  made  slightly  acid  with  HC1 , and  the 
sulfate  precipitated  out  with  10  cc.  of  a hot  10 $ BaClg  solution. 

Bitrogen . 

Analyses  for  nitrogen  were  made  on  Gilsonite  Select,  and  as- 
phaltene by  the  Xjeldahl- Gunning  Method,  using  1 gram  of  material, 

30  cc.  concentrated  HgS0A , .6-. 8 grams  of  CuSO^.  in  the  digestion, 
and  KMhC'4  crystals  were  added  after  the  digestion  to  insure  com- 
plete oxidation.  The  following  results'  were  obtained: 

Tabl e XIII.  H it  rog  en . 

Gilsonite  Select  Asphaltene 

2.51$  1.48$ 

2.49  1.53 

Carbon  , Hydrogen , and  Oxygen  Analysis . 

An  analysis  for  0,  II,  and  0 was  made  on  a sample  of  asphaltenes  , 
and  the  following  result  obtained  on  a .5  gram  sample  of  the  materia 
Carbon  Hydrogen  Oxygen 

44,87$  5.25 $ 47.39$ 

A sample  ultimate  analysis  of  the  asphaltene  would  be: 

”fc 

Carbon  Hydrogen  Oxygen  Biro gen  Sulfur 
44.87$  5.25$  47.39$  1.53$  .96$ 


- 


* 


18- 


This  -ultimate  analysis  shows  that  asphaltenes  to  be  the  result  of 
continued  action  of  oxygen  on  petroleum  resins,  because  of  the  high 
percentage  of  oxygen  present.  It  shows  them  to  contain  3 and  H 
in  appreciable  quantities. 

lliscellaneous  Tests  t 

The  asphaltene  will  reduce  aqueous  EMhO^  on  continued  boiling 
and  standing  for  several  hours. 

They  have  no  diazo  reaction,  or  anthraquinone  reaction. 

They  have  a trace  of  saponifiable  natter. 


. 


19- 


ORIGrlM  OP  ASPHALTEIES,  THEIR  PROPERTII  AID  COMPOSITE 01 
Asphaltenes  may  be  formed  by  continued  action  of  oxygen  or 
sulfur  on  petroleum  resins,  or  by  atomic  rearrangement.  The  resins 
formed  on  heating  heavy  mineral  oils  in  air  are  gradually  trans- 


formed into  asphaltenes  by  continued  heating. 

Properties  of  Asphaltenes . 

Externally,  the  asphaltenes  are  a brownish-black  pov/der,  do  not 
melt , but  swell  up  on  heating  , decomposing  and  leaving  a coke  that  ; 
is  very  difficultly  combustible.  They  yield  no  distillate  on  heat- 
ing. They  are  almost  insoluble  in  alcohol  and  benzine,  slightly 
soluble  in  ether  and  acetone,  but  are  complete!;,  soluble  in  C^Hg, 
CHGlg , and  CSg.  The  asphaltenes  of  natural  asphalts  are  character- 
ized by  their  high  sulfur  content.  The  sulfur  compounds  are  very 
sensitive  to  light,  being  transformed  into  an  insoluble  modification 

Chemistry . 

On  being  treated  with  fuming  nitric  acid  at  -1C°C.,  the  as- 
phaltene may  be  converted  into  nitro  compounds  wh'  ch  dissolves  in 
alcoholic  KOH.  On  heating,  we  have  nitrous  acid  split  off.  HgSOA 
and  HCHO  form  insoluble  salts. 

The  iodine  number  of  asphaltene  is  very  high,  52.6.  The  Br 
substitution  number  is  4.8.  It  is  not  to  be  concluded  however, 
that  we  have  unsaturated  bodies  in  the  asphaltenes,  as  the  HgpBiv 
test  shows  that  they  contain  sulfides  which  may  take  up  Br. 

( 2Br  = 13) 

format! on  and  Composition  of  Asphal t Constituent 3 . 

1.  Oily  constituents. 

2.  Petroleum  resins. 

3.  Asphaltenes. 

4.  Asphaltous  acids. 


The  oily  portions  separated  from  natural  asphalts  resemble 


20- 


viscous  fluorescent  mineral  oils.  They  show  optical  activity. 

Concentrated  H0SO4.  takes  asphaltenes  in  solution  at  1G0°C.  , 
providing  all  solvents  are  absent , then  the  solution  becomes  black, 
and  pasty,  with  the  evolution  of  SOg.  On  pouring  into  water, 
black  products  sparingly  soluble  in  pyridine  form;  heating  with 
dilute  HC1  splits  off  HgSQ^.  The  products  of  H^SO^  and  asphaltenes 
in  the  cold  probably  indicate  the  formation  of  an  oxonium  or 
sulfonium  compound. 

On  treating  a benzene  solution  of  asphaltene  with  concent  rated 
sulfuric  acid  at  room  temperature , the  precipitation  was  almost 
quantitative  , the  precipitate  having  the  appearance  of  the  original 
asphaltene,  with  the  exception  that  the  precipitate  was  flocculent 
in  appearance.  The  precipitate  was  washed  out  with  HgSO^ , and 
v/as  found  to  be  almost  insoluble  in  benzene.  Heating  had  no  effect 
on  the  solubility  for  asphaltenes  are  freely  soluble  in  cold  benzene. 
This  indicates  the  formation  of  double  compounds.  Polymerisation 
has  taken  place,  and  an  HgSO^  compound  was  probably  formed,  for 
on  heating  with  dilute  HOI,  HgSO^.  was  given  off.  When  testing 
the  solubilities  of  the  compound  it  was  found  to  be  insoluble  in 
ITH^OH,  alcoholic  KOH,  but  soluble  in  pyridine.  The  pyridine  solu- 
tion mixed  freely  with  water,  arid  on,  shaking  yields  a foam  similar 
to  soap  solution.  On  the  addition  of  water,  a precipitate  of  the 
original  asphaltenes  was  obtained. 

Sulfuric  acid,  in  the  cold,  as  we  have  seen  before,  indicates 
the  production  with  asphaltenes  0 f an  oxonium  or  sulfonium  compound 
The  corresponding  ether  compound  shows  the  property  of  a salt,  and 
is  a weak  acid,  due  to  the  OH  group,  and  is  analogous  to  the 


- 

p * 

. 

• 

* 

• 

* 

21- 


asphalt  sulfur  compound.  The  ether  has  the  following  formula: 


sulfate,  so  the  action  of  sulfuric  acid  on  asphaltene  at  1C0°G., 
except  that  there  might  he  a possibility  for  the  formation  of  a new 
closed  ring  due  to  the  union  of  the  free  OH  of  the  primarily  formed 
H2S04  compound  with  a nuclear  H atom  yielding  water. 

Asphaltenes  are  polycyclic  compounds,  which  contain  G,  H,  S, 
and  0 in  the  ring  form  or  as  sulfides  or  ether;  3 and  0 may  re- 
place one  another.  A. sphaltene  is  higher  in  S and  0 than  the 
resins.  Asphalts  may  he  formed  from  unsaturated  or  saturated 
compounds;  the  former  are  mainly  naphthalenes  and  terpenes,  since 
aliphatic  hydrocarbons  occur  only  to  a small  extent  in  petroleum. 
The  reaction  between  unsaturated  hydrocarbons  and  3 and  0 takes 
place  according  to  the  Engl er  Aut oxidation  Theory. 

A Bakelite  condensation  was  tried  on  a sample  of  asphaltenes 
obtained  from  G-ilsonite.  The  procedure  was  as  follows:  the  as- 

phaltenes were  shaken  up  in  an  alcoholic  KOH  solution.  Hexamethy- 
lene  tetramine  was  added  and  the  mixture  refluxed  on  an  electric 
hot  plate  for  8 hours.  The  apparatus  used  was  one  as  described 
in  the  accompanying  figure,  (JFig.  3). 


Just  as  ether,  HgBO^  at  100°C.,  forms  small  amounts  of  diethyl 


22- 


fhe  substance  after  refluxing,  was  neutr  lized  with  HgSO^.  Ifore 
hexamethylene  tetramine  was  added,  and  the  product  salted  out  with 
UH4CI.  The  results  were  negative.  Ho  condensation  product 
was  formed,  and  according  to  Baekeland,  this  condensation  will 
not  work  where  the  OH  is  in  the  ring,  it  must  he  in  the  sice  chain 
for  the  condensation  to  take  place. 


SUMMARY 


23- 


1.  The  percentage  of  asphaltenes  in  certain  "bitumens  is  sig- 
nificant because  it  helps  determine  the  nature  of  the  asphalt.  In 
general,  it  might  be  said,  that  the  higher  the  percentage  of  as- 
phaltene present  in  a petroleum  product,  in  Gilsonite,  in  coal,  or 
any  other  bituminous  material,  the  more  asphaltic  is  its  character, 
and  specifications  sometimes  make  use  of  this  test  in  order  to  se- 
cure a highly  asphaltic  content. 

2.  That  the  differences  between  Gilsonite  and  Gilsonite  Select 
is  in  the  difference  betwe  n the  percentages  of  asphaltenes.  Gil- 
sonite containing  approximately  45$,  Gilsonite  Select  11.2$. 

3.  The  analysis  of  asphalts  by  the  Selective  Solvent  Method 
has  its  disadvantages  because  the  composition  of  asphalts  is  not 
uniform  and  the  composition  of  the  solvents  does  not  remain  constant, 

4.  Asphaltenes  may  be  found  in  petroleum  residues,  pitch  from 
coke  ovens,  and  natural  asphalts.  This  may  give  us  a clue  or  an 
insight  into  the  common  properties  which  certain  bituminous  materials 
possess.  it  may  oring  to  light , the  fact  that  these  bituminous 
materials  are  all  of  a common  origin  representing  different  stages 

in  car oonizat ion  or  condensation.  Asphaltenes  may  be  a connecting 
link  between  coal,  asphalt,  and  petroleum.  The  asphaltenes  of 
crude  oil  and  native  asphalts  are  closely  related  to  coal.  A 
transformation  theory  for  bituminous  or  asphaltic  material  may  throw 
some  ligit  on  this  relation. 

Goal;-  Peat  Lignite  Bituminous  Anthracite 

Petroleum;-  Petroleum  R esins  Asphaltenes  Oarbenes 

Garbo ids . 

5.  uinoe  asphaltenes  take  up  5 so  readily  it  might  be  concluded 


*8 

. 

. 


24- 


that  the  sulfur  and  oxygen  are  present  in  a ring  structure  rather 
than  if  the  form  of  ether  or  sulfides. 

6.  Since  the  uses  of  asphalt,  asphalt  residues,  flukes  and 
binders  both  natur  1 and  artificial  has  increased  tremendously 
in  the  last  few  years,  a chemical  examination  is  almost  imperative. 


BIBLIOGRAPHY 


1.  Linton,  Laura  A.  J.  Am.  Chem.  Soc . 16,-809. 

18,-275. 

2.  Boussingault , J.  B.  Ann.  de  Chim.  et  Phys . 64,-141. 

3.  Babin,  J.  Am.  Chem.  Soc.  18,-283. 

4.  Marcus  son,  A.  and  Eichman  R.  Chem.  Zeit.  32,-965. 

5.  Richardson,  Clifford,  J.  Ind . and  Eng.  Chem.  8,-493-4. 

6.  Sommer,  Albert,  J.  Ind.  and  Eng.  Chem.  2,-18. 

7.  Richardson,  Clifford  and  Forrest,  C.  i' . J.  Soc.  Chem.  Ind 

24,-310. 

8.  Avery  and  Corr,  J.  A.  C.  3.  28,-648. 

9.  Bornemann,E.  Chem.  Zeit.  33,-970. 

10.  Meyerheim,  G.  " " 34,-454-5. 

11.  Hubbard,  P and  Reeves,  C.  S.  Chem.  Eng.  12,-15. 

12.  Lohmann,  L.  Chem.  Zeit.  35,-357-8. 

13.  Lobell,  Chem.  Zeit.  36, -4-5. 

14.  Marcusson,  J.  do.  36,-22-3. 

15.  do  38,-813-4. 

16.  Lay,  J.  Frank.  Inst.  Sept.  1895. 

17.  Lunge , G.  and  Krepelka,  Y.  J.  Soc.  Chem.  Ind.  1904,  436. 

18.  Parr,  3.  Y. , Mears , B.  , and  Weatherhead,  J.  Ind.  and  Eng. 

Chem.  Vol . 1,  #11,  Lov.  1909. 

19.  LeBel , Bull.  Soc.  Chim.  50,-359. 

20.  Endemann,  J.  Soc.  Chem.  Ind.  1896,  874. 

21.  Holde  , ’’Examination  of  Hydrocarbon  Oils.” 

22.  Abraham,  "Asphalts  and  Allied  Substances." 

23.  Hubbard,  "Lust  Preventives  and  Road  Binders." 


26- 


24.  Hubbard,  "Highway  Inspectors  Handbood." 

25.  Sadtler,  "Industrial  Organic  Chemistry." 

26.  Campbell,  "Petroleum  Refining.” 

27.  Boo rman , "As phal t s . " 

28.  Hamor  and  Padgett,  "The  Examination  of  Petroleum." 


- 


. 


\ 


\ 


